7 9 
circle, it will be perceived that the curve 
of the arch can no how be diminished in 
one place without being proportionably 
increased in another, so long as the part 
nearest the equator remains with the same 
curvation as that of the parallel of latitude 
along the equator. But in case the polar- 
end of the wax arch be extended outwards 
from the centre beyond the true circle, 
then the curve of that end will be ex¬ 
panded without any reduction of the cur¬ 
vature of any other part of it. Hence an 
opinion is justified (which I trust the pre¬ 
ceding principles will go to show is cor¬ 
rect) that the arch of wax should be bent 
outwards towards its north end, in order 
to gradually lengthen the degrees from 
the equator, as far as the polar circle— 
which is as far as we can prove that they 
do lengthen, for no farther have they been 
measured, and that it should afterwards 
be bent inwards in an unknown quantity, 
somewhere beyond that circle, if we con¬ 
clude the earth to appear, when seen from 
other planets, to be in any degree flatted 
at the poles like Jupiter. 
How or where the meridians of the 
earth terminate, cannot be indisputably 
determined, until we have seen or ex¬ 
plored her surface to their termination. 
JOHN CLEVES SYMMES. 
j Newport, Ky. Dec. 27, 1820. 
(H7* Were the earth ascertained to be a true 
sphere, the circumstance of the atmosphere 
being gradually more dense in advancing to¬ 
wards the poles, so as progressively to increase 
the quantity of refraction in such direction ; we 
would be compelled to pass through a larger 
arch of the surface of the earth at the polar 
circle, to measure a degree in the heavens (and 
there it is, that we measure our degrees) than 
would be requisite at the equator; and the in- 
j crease would be gradual and proportioned to the 
. distance from the equator. If this principle be 
admittelh to exist, throughout the planetary 
; system, i^,would follow by induction, that the 
planets appear to us less flatted at their 
; j 10 * 68 dian they really are, as well as appear 1 
j ar £ er every way than they would if they had 
j fto atmosphere around them. 
